Parallel or Series PV: Midnite Kid to charge Boathouse Battery Bank

Here’s what I’m considering.

Installing 200 +/- Ah battery bank with 500 watt (2 panels) PV array at a covered boat dock. Pretty much settled on the Midnite Kid charger and will decide on panels and batteries according to best price. The Kid can handle either configuration (parallel or series) for standard panels, but I’m not sure which way to go. The cost of the equipment to configure either configuration seems to a wash, I’ll use an inexpensive MC4 Y connector to make the parallel so that I still deal with single positive/negative wiring into the PV disconnect/ground fault panel. I know this ain’t rocket science, but anybody there who would like to chime in? I’m thinking, is it better for this application to have 16-17 amps (with some 30 volts) going to the Kid rather than 8-9 amps and 50-60 volts. I have plenty of heavy wire left over from other projects, so wire gauge is not an issue. The PV runs are short, about 10 feet from array to PV panel and 18-20 feet to the Kid charger. The whip to the batteries would be about 10 feet directly out of the Kid (with inline fuse and disconnect) and the load panel (3 circuits max) will be mounted right next to the Kid charger. 

The final objective is to mount the 200 +/- Ah battery bank on a pontoon boat to run an electric trolling motor and to operate “house” lighting at night. The Kid will recharge batteries during daylight hours and provide some pre-set dusk time lighting at night. Any thoughts on configuring such an set-up appreciated. 

Thanks.